tab_separator_lines.css ineffective on Linux

[ceodoe]

trafficstars

tab_separator_lines.css doesn't seem to work on Linux. My load order is as follows:

@import url("chrome/compact_proton.css");
@import url("chrome/non_floating_sharp_tabs.css");
@import url("chrome/tab_separator_lines.css");
@import url("chrome/iconized_main_menu.css");
@import url("chrome/inline_tab_audio_icons.css");
@import url("chrome/autohide_bookmarks_and_main_toolbars.css");
@import url("chrome/compact_urlbar_megabar.css");

...although changing the load order doesn't seem to make any difference. Disabling all other styles also doesn't do anything. Using Firefox 89.0+build2-0ubuntu0.20.04.2 amd64 from Ubuntu Focal repo. Any ideas? 🤔

[mlantas]

I noticed the same thing on Windows.

My workaround was to use some of the old photon CSS:

.titlebar-spacer[type="pre-tabs"] {
	border-inline-end: 1px solid
		var(--lwt-background-tab-separator-color, currentColor);
	opacity: 0.2;
}

.tabbrowser-tab::after,
.tabbrowser-tab::before {
	border-left: 1px solid
		var(--lwt-background-tab-separator-color, currentColor);
	opacity: 0.3;
}

.tabbrowser-tab::before {
	margin-inline-start: -1px;
}

.tabbrowser-tab::after,
#tabbrowser-tabs[movingtab]
	> #tabbrowser-arrowscrollbox
	> .tabbrowser-tab[visuallyselected]::before {
	content: "";
	display: block;
}

[MrOtherGuy]

You may need to go to about:config and enable layout.css.color-mix.enabled which is not enabled yet on release Firefox I think. If that doesn't work then I'll test more tomorrow.

Thanks for reporting anyway.

[mlantas]

enable layout.css.color-mix.enabled

This works for me!

[ceodoe]

Works for me as well, thanks!

[MrOtherGuy]

Great to hear. But damn, I thought color-mix was enabled in 89 by default but it's not. Bunch of things will require it,